Refiner for wood pulp



REFINER FOR WCUD PULP Filed May 15, 1917 B /xl A' B Patented Apr. 8, 1924.

UNITED STATES EINAR WAHLSTRM, or

PATENT OFFICE.

RIElIEINEIEtV FOR WOOD PULP.

Application :filed May 16, 1917.

Serial No. 169,040'95.

(GRANTED UNDER THE PROVISIONS F THE ACT 0F MARCH 3, 1821, 41 STAT. L., 1313.)

To all whom it may concern.'

Be it lniown that I, EINAR. VAHLSTRM, a subject of the King of Norway, residing at Vittingfos, in the Kingdom of Norway,

6 have invented certain new and useful Improvements in Refiners for Wood Pulp (for which I have filed an application in Norway May 9, 1916, Patent No. 27,544); and

I do hereby declare the following to be a full, 10 clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification.

The present inventionrelates to refiners for wood pulp and has for its object a particular arrangement for mounting the bed stone or stones.

The invention may be applied on refiners with vertical as well as horizontal axis but is particularly adapted for refiners of the last named type.

In order to avoid the vibrations easily produced with stones supported in the ordinary way by screws, which vibrations act to lessen the efficiency and cause uneven grinding, and in order to at the same time always keep the charging chamber automatically open, the bed stone or stones according to the present invention are mounted on a pivot located on the inlet side, so that the edge of the bed stone at the inlet lies l outside the connecting line between the axis of the refining stone and the pivot of the bed stone.

On the drawing is shown a diagrammatical section through a form of the invention as applied on a rener with horizontal axis, the bedding of which consists of two stones, one over and one below the rotating grinding stone.

The bed stones A are placed in frames B supported on one side by trunnions C and on the opposite side in the usual manner by screws D. E are the inlets and F the outlets for the pulp. The bearings for the trunnions C should be vertically adjustable so that they may be adjusted in accordance with the wear of the stones.

In refiners constructed in this way the rotating stone will exert a pull on the bed stone in the direction from its trunnions, the screws for the adjustment will therefore not be exposed to lateral stress and vibrations as is the case in refiners the bed stones of which are supported with four screws. rI`he increasing pressure between the stones towards the outlet and the fact that the inlet space is widened by tightening the screws, combine to increase the efiiciency of this refiner.

I claim:

l. In refiners for wood pulp a bed stone pivotally supported near the pulp inlet in such a manner, that the inlet edge of the bed stone is removed from the grinding surface when the opposite side of the bed stone is moved towards the grinding surface whereby the inlet space is automatica-lly kep-t open, while the pressure is steadily increased towards the outlet.

2. A refiner for wood pulp comprising a rotary grinding member and a cooperating bed member mounted in pivoted relation to the rotary member, said cooperating member having its .inlet edge in front of a plane extending through the axis of the rotary member and the pivotal axis of the bed member.

In testimony that I claim the foregoing as my invention, I have signedmy name in presence of two subscribing witnesses.

EINAR VAHLSTROM.

IVtnesses Dn VORMAN, HARRY EDWIN CARLSON. 

